extends Node
## Render actual presentation materials from both sides; headless cannot prove visibility.
var checks: int = 0
var failures: Array[String] = []

func check(ok: bool, label: String) -> void:
	checks += 1
	if not ok:
		failures.append(label)
		printerr("MATERIAL_FAIL: ", label)

func _ready() -> void:
	call_deferred("run")

func run() -> void:
	if DisplayServer.get_name() == "headless":
		printerr("This material test requires a rendering display.")
		await Soundscape.quit_game(1)
		return
	Soundscape.enabled = false
	var view := SubViewport.new()
	view.size = Vector2i(512, 256)
	view.own_world_3d = true
	view.render_target_update_mode = SubViewport.UPDATE_ALWAYS
	add_child(view)
	var world := WorldEnvironment.new()
	world.environment = Environment.new()
	world.environment.background_mode = Environment.BG_COLOR
	world.environment.background_color = Color(.01, .01, .01)
	world.environment.ambient_light_source = Environment.AMBIENT_SOURCE_COLOR
	world.environment.ambient_light_color = Color.WHITE
	world.environment.ambient_light_energy = 1.0
	world.environment.reflected_light_source = Environment.REFLECTION_SOURCE_DISABLED
	view.add_child(world)
	var camera := Camera3D.new()
	camera.projection = Camera3D.PROJECTION_ORTHOGONAL
	camera.size = 2.4
	camera.position = Vector3(0, 0, 3)
	view.add_child(camera)
	var front := MeshInstance3D.new()
	front.mesh = QuadMesh.new()
	front.position.x = -.6
	view.add_child(front)
	var back := MeshInstance3D.new()
	back.mesh = front.mesh
	back.position.x = .6
	back.rotation.y = PI
	view.add_child(back)
	var source: Node3D = load("res://assets/characters/quellgeflecht.glb").instantiate()
	var surfaces: Dictionary = {}
	for node: Node in source.find_children("*", "MeshInstance3D", true, false):
		for index: int in range(node.mesh.get_surface_count()):
			var material: Material = node.get_active_material(index)
			if material.resource_name in ["QG_Leaf", "QG_Moss", "QG_Petal"]:
				surfaces[material.resource_name] = material
	check(surfaces.size() == 3, "all three imported foliage materials present")
	var measurements: Dictionary = {}
	for key: String in surfaces:
		var original: StandardMaterial3D = surfaces[key]
		check(original.cull_mode == BaseMaterial3D.CULL_DISABLED, key + " authored double-sided")
		var material: Material = AssetLibrary.presentation_material(original)
		front.material_override = material
		back.material_override = material
		for frame in range(5):
			await get_tree().process_frame
		await RenderingServer.frame_post_draw
		var pixels := view.get_texture().get_image()
		var front_pixel := camera.unproject_position(front.position)
		var back_pixel := camera.unproject_position(back.position)
		var front_light := pixels.get_pixelv(Vector2i(front_pixel)).get_luminance()
		var back_light := pixels.get_pixelv(Vector2i(back_pixel)).get_luminance()
		check(front_light > .15, key + " front is visible")
		check(back_light > .15, key + " reverse side is visible")
		check(absf(front_light - back_light) < .08, key + " sides have consistent ambient lighting")
		measurements[key] = {"front_luminance": front_light, "back_luminance": back_light}
		pixels.save_png("res://docs/screenshots/phase17/" + key.to_lower() + "-sides.png")
	source.free()
	var report := FileAccess.open("res://docs/phase17-material-verification.json", FileAccess.WRITE)
	report.store_string(JSON.stringify({"checks": checks, "failures": failures, "renderer": RenderingServer.get_current_rendering_method(), "materials": measurements}, "\t"))
	report.close()
	print("MATERIAL_PASS: ", checks, " checks; ", failures.size(), " failures")
	await Soundscape.quit_game(0 if failures.is_empty() else 1)